Primary Calibration of Solar Photovoltaic Cells At the National Metrology Centre of Singapore

A multi-functional differential spectral responsivity (DSR) measurement system for primary calibration of the shortcircuit current (SCC) of reference solar cells with WPVS (World Photovoltaic Scale) design [1] is reported in this paper. Based on the dual beam principle, the system is able to measure DSR at different bias levels, spatial uniformity, linearity, temperature coefficient of the spectral responsivity of reference cells in the spectral range from 280 nm to 1200 nm. The measurement principle, system design and construction as well as the performance of the system are described in this work. An uncertainty ≤ 1% for SCC measurement is confirmed by experimental results.